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Updated: Aug 29, 2026

Assessing Differences in Sperm Competitive Ability in Drosophila
Published on: August 22, 2013
Does female mortality drive male semelparity in dasyurid marsupials?
Ken Kraaijeveld1, Femmie J L Kraaijeveld-Smit, Greg J Adcock
1Department of Biology, Galton Laboratory, University College London, Wolfson House, 4 Stephenson Way, London NW1 2HE, UK. k.kraaijeveld@ucl.ac.uk
Abstract:
In some members of the marsupial families Didelphidae and Dasyuridae, males are semelparous, that is, they live for only one mating season. Semelparity is proposed to be the result of the high energy demands of competing for matings with many females during a short breeding season. We argue that high adult female mortality rates between mating and weaning of the offspring selects for a 'bethedging' mating strategy in males. We tested this hypothesis in a well-studied field population of Antechinus agilis by estimating the number of females a male needs to mate with in order to have a high chance of siring at least one offspring that survives to the next breeding season. Our hypothesis predicts that species in which males are semelparous should have higher female mortality rates than species in which males are iteroparous. The limited available data for dasyurid marsupials support this prediction.
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